.458 SOCOM
Encyclopedia
The .458 SOCOM is a relatively large round designed for a specialized upper receiver that can be mounted on any AR-15
pattern rifle. The 300 gr round offers a muzzle velocity 1900 ft/s (579.1 m/s) and 2405 ft.lbf.
community, specifically Task Force Ranger's experience that multiple shots were required to neutralize members of the opposing force in Mogadishu
during Operation Gothic Serpent
. Marty ter Weeme designed the cartridge in 2000 and Tony Rumore of Tromix, Inc was contracted to build the first .458 SOCOM rifle in February 2001.
The project sponsor set forth a number of specific requirements that led to the ultimate design as it stands right now: The cartridge had to fit in the M-4 platform and magazines, be capable of firing heavy-for-caliber projectiles at subsonic velocity using suppressors. During the developments phase, various other cartridges were considered and proposed to the project sponsor, but rejected as not meeting all the requirements. The cartridges considered were 7.62×39mm M43, 9×39mm Grom, .45 Professional (which has since become the .450 Bushmaster
), and .50 Action Express
. At the time, the .499 LWR cartridge was still in development phase and had not been chambered commercially.
The .45 Professional was ruled out because in an interview with industry press, the developer of said cartridge stated that steel proprietary to General Motors
was used in the bolts and extensions to withstand the high operating pressures. The .50 AE and .499 LWR were ruled out because in 2000 only two bullets were offered in .501 diameter, both developed as pistol bullets for the .50 AE and not heavy enough for the subsonic suppressed role. Research had indicated that a short belted cartridge called the .458 × 1.5" Barnes had been adopted for use in suppressed bolt action rifles for use in SE Asia during the Vietnam War
. It was shown as effective in terms of ballistics, firing a 500 grain bullet subsonically, but not ideally suited for its role due to the size and weight of the platform. Combined with the wide selection of bullets available in .458 diameter, this cemented the choice of caliber.
The cartridge case design was finalized based on discussions with Tony Rumore at Tromix, Inc. suggesting a lengthened .50 AE case would work well in the magazines as well as be the largest diameter case to be able to feed through the barrel extension. The rim size was chosen for compatibility with other platforms, primarily bolt action rifles, as the .473" diameter rim is arguably the most common rim size globally (all bolt actions chambered in 7.92×57mm Mauser
, .30-06 Springfield
or .308 Winchester
share this rim size). The case length was chosen to be compatible with the Barnes 300-grain X Spitzer
bullet. In 2009, Barnes developed a new bullet specifically for use in the .458 SOCOM, the 300 grain Tipped Triple Shock X, also known as the TTSX or TAC-X.
Another website dedicated to the 458SOCOM platform. Load data and other info also available
The458SOCOM.com
AR-15
The AR-15 is a lightweight, 5.56 mm, air-cooled, gas-operated, magazine-fed semi-automatic rifle, with a rotating-lock bolt, actuated by direct impingement gas operation. It is manufactured with the extensive use of aluminum alloys and synthetic materials....
pattern rifle. The 300 gr round offers a muzzle velocity 1900 ft/s (579.1 m/s) and 2405 ft.lbf.
History
Inspired by a lack of power offered by the 5.56 NATO cartridge used in the M4 and the M16, the .458 SOCOM came about from informal discussion of members of the special operationsSpecial operations
Special operations are military operations that are considered "special" .Special operations are typically performed independently or in conjunction with conventional military operations. The primary goal is to achieve a political or military objective where a conventional force requirement does...
community, specifically Task Force Ranger's experience that multiple shots were required to neutralize members of the opposing force in Mogadishu
Mogadishu
Mogadishu , popularly known as Xamar, is the largest city in Somalia and the nation's capital. Located in the coastal Benadir region on the Indian Ocean, the city has served as an important port for centuries....
during Operation Gothic Serpent
Operation Gothic Serpent
Operation Gothic Serpent was a military operation conducted by special operations forces of the United States with the primary mission of capturing warlord Mohamed Farrah Aidid...
. Marty ter Weeme designed the cartridge in 2000 and Tony Rumore of Tromix, Inc was contracted to build the first .458 SOCOM rifle in February 2001.
The project sponsor set forth a number of specific requirements that led to the ultimate design as it stands right now: The cartridge had to fit in the M-4 platform and magazines, be capable of firing heavy-for-caliber projectiles at subsonic velocity using suppressors. During the developments phase, various other cartridges were considered and proposed to the project sponsor, but rejected as not meeting all the requirements. The cartridges considered were 7.62×39mm M43, 9×39mm Grom, .45 Professional (which has since become the .450 Bushmaster
.450 Bushmaster
The .450 Bushmaster is a rifle cartridge developed by Tim LeGendre of LeMag Firearms LLC, and licensed to Bushmaster Firearms International for production and distribution. LeGendre still retains ownership of the concept...
), and .50 Action Express
.50 Action Express
The .50 Action Express is a large caliber handgun cartridge. It was developed in 1988 by Evan Whildin of Action Arms. The .50 AE is one of the most powerful pistol cartridges in production.-Overview:...
. At the time, the .499 LWR cartridge was still in development phase and had not been chambered commercially.
The .45 Professional was ruled out because in an interview with industry press, the developer of said cartridge stated that steel proprietary to General Motors
General Motors
General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...
was used in the bolts and extensions to withstand the high operating pressures. The .50 AE and .499 LWR were ruled out because in 2000 only two bullets were offered in .501 diameter, both developed as pistol bullets for the .50 AE and not heavy enough for the subsonic suppressed role. Research had indicated that a short belted cartridge called the .458 × 1.5" Barnes had been adopted for use in suppressed bolt action rifles for use in SE Asia during the Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
. It was shown as effective in terms of ballistics, firing a 500 grain bullet subsonically, but not ideally suited for its role due to the size and weight of the platform. Combined with the wide selection of bullets available in .458 diameter, this cemented the choice of caliber.
The cartridge case design was finalized based on discussions with Tony Rumore at Tromix, Inc. suggesting a lengthened .50 AE case would work well in the magazines as well as be the largest diameter case to be able to feed through the barrel extension. The rim size was chosen for compatibility with other platforms, primarily bolt action rifles, as the .473" diameter rim is arguably the most common rim size globally (all bolt actions chambered in 7.92×57mm Mauser
7.92x57mm Mauser
The 8×57mm IS is a rimless bottlenecked rifle cartridge. The 8×57mm IS was adopted by the German Empire in 1905, and was the German service cartridge in both World Wars...
, .30-06 Springfield
.30-06 Springfield
The .30-06 Springfield cartridge or 7.62×63mm in metric notation, was introduced to the United States Army in 1906 and standardized, and was in use until the 1960s and early 1970s. It replaced the .30-03, 6 mm Lee Navy, and .30 US Army...
or .308 Winchester
.308 Winchester
The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...
share this rim size). The case length was chosen to be compatible with the Barnes 300-grain X Spitzer
Spitzer (bullet)
A spitzer, also commonly referred to as a spire point bullet, is an aerodynamic bullet design used in most intermediate and high-powered rifle cartridges...
bullet. In 2009, Barnes developed a new bullet specifically for use in the .458 SOCOM, the 300 grain Tipped Triple Shock X, also known as the TTSX or TAC-X.
See also
- List of rifle cartridges
- 11 mm caliber11 mm caliberThis article lists firearm cartridges which have a bullet in the through caliber range.All measurements are in millimeters .-Pistol cartridges:-Revolver cartridges:-Rifle cartridges:-See also:...
- .458 Winchester Magnum.458 Winchester MagnumThe .458 Winchester Magnum is a belted, straight-taper cased, dangerous game rifle cartridge. It was introduced commercially in 1956 by Winchester and first chambered in the Winchester Model 70 African rifle. It was designed to compete against the .450 Nitro Express and the .470 Nitro Express...
- .50 Beowulf.50 BeowulfThe .50 Beowulf [12.7×42 mm Rb] is a rifle cartridge developed by Alexander Arms for use in a modified AR-15 rifle. The cartridge utilizes a rebated rim, sized to match the rim of the 7.62×39mm and 6.5 mm Grendel rounds...
- .50 Alaskan.50 AlaskanThe .50 Alaskan is a wildcat cartridge developed by Harold Johnson and Harold Fuller of the Kenai Peninsula of Alaska in the 1950s. Johnson based the cartridge on the .348 Winchester in order to create a rifle capable of handling the large bears in Alaska....
External links
- Ralph M. Lermayer, Rifle Review:.458 SOCOM, military.com
Another website dedicated to the 458SOCOM platform. Load data and other info also available
The458SOCOM.com